ADCX-020 for the Treatment of Patients With Locally Advanced or Metastatic Cancers

Inclusion Criteria: * Male and female participants ≥ 18 years of age * Ph1a: Locally advanced or metastatic solid tumor relapsed or PD following local standard treatments, for which no standard treatment is available * Ph1b: Eligible patients should have only received prior lines of systemic therapy according to SoC in the advanced/metastatic setting (not counting neoadjuvant/adjuvant treatment if completed \>6 months prior to recurrence) * Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1 * Radiologically measurable disease by RECIST v1.1 * Mandatory adequate tumor tissue sample available * Must have recovered from all clinically relevant toxicities from previous cancer therapies (to at least Grade 1, except for alopecia) Exclusion Criteria: * Known allergies/hypersensitivity/intolerance to or contraindication to exatecan, or any excipient * Phase 1b: Prior antibody drug conjugate exposure with a topoisomerase 1 inhibitor payload * Uncontrolled or significant cardiac disease including left ventricular ejection fraction (LVEF) \<50%, myocardial infarction or uncontrolled/unstable angina * Has clinically active central nervous system (CNS) metastases * Has a history of lung fibrosis or non-infectious interstitial lung disease (ILD)/pneumonitis that required steroids, has current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at screening * Active corneal disease, or history of corneal disease within 12 months prior to enrollment * Other unacceptable abnormalities, medications or procedures as defined by protocol